Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 417 AM EDT Mon Jul 15 2024 Valid 12Z Mon Jul 15 2024 - 12Z Wed Jul 17 2024 ...There is an Enhanced Risk of severe thunderstorms over parts of the Middle Mississippi Valley/Western Ohio Valley into the Great Lakes on Monday and a Slight Risk of severe thunderstorms over parts of the Eastern Ohio Valley/Lower Great Lakes/Northeast and over portions of the Central High Plains on Tuesday... ...There is a Slight Risk of excessive rainfall over parts of the Middle Mississippi Valley into the Great Lakes on Monday and the Middle Mississippi Valley to Ohio Valley on Tuesday... ...There are Excessive Heat Warnings/Watches and Heat Advisories over parts of the Mid-Atlantic to New England and over parts of Central/Southern Plains and Middle/Lower Mississippi Valley and parts of the Western Ohio Valley/Western Tennessee Valley... A front extending from the Great Lakes across the Middle Mississippi Valley into the Northern Plains will move to the Lower Great Lakes/Ohio Valley across the Middle Mississippi Valley and trail off into the Northern Plains by Wednesday. A wave of low pressure over the Northern Plains will move northeastward to the Upper Great Lakes by Monday evening, bringing the cold front northward into the Upper Great Lakes to the Middle Mississippi Valley/Central Plains. On Monday, the boundary will produce showers and severe thunderstorms over the Middle Mississippi Valley/Western Ohio Valley into the Great Lakes. Therefore, the SPC has issued an Enhanced Risk (level 2/5) of severe thunderstorms over parts of the Middle Mississippi Valley/Western Ohio Valley through Tuesday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Moreover, there is an increased threat of severe thunderstorm wind gusts of 65 knots or greater, mainly over parts of the Middle Mississippi Valley/Western Ohio Valley. In addition, the showers and thunderstorms will create heavy rain over parts of the Middle Mississippi Valley into the Great Lakes. Therefore, the WPC has issued a Slight Risk (level 2/4) of excessive rainfall over parts of the Middle Mississippi Valley into the Great Lakes through Tuesday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, small streams, and low-lying areas the most vulnerable. Furthermore, on Monday, upper-level energy and tropical moisture will produce showers and thunderstorms from parts of the Central Gulf Coast eastward to the Southeast. Additionally, moisture over the Southwest and diurnal heating will produce late afternoon into late evening showers and thunderstorms over parts of the Great Basin, Southwest, and Central/Southern Rockies. On Tuesday, the threat of severe thunderstorms reduces slightly. As the front moves eastward, showers and severe thunderstorms will develop over parts of the Eastern Ohio Valley, Lower Great Lakes, and Northeast. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over parts of the over parts of the Eastern Ohio Valley/Lower Great Lakes/Northeast from Tuesday through Wednesday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Furthermore, showers and thunderstorms will produce heavy rain over parts of the Middle Mississippi Valley to Ohio Valley. Therefore, the WPC has issued a Slight Risk (level 2/4) of excessive rainfall over parts of the Middle Mississippi Valley to Ohio Valley from Tuesday through Wednesday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, small streams, and low-lying areas the most vulnerable. Moreover, as the western end of the front moves across the Central High Plains, showers and severe thunderstorms will develop over the region. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over parts of the over parts of the Central High Plains from Tuesday through Wednesday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a minimal threat of tornadoes. Also, upper-level energy and tropical moisture will produce showers and thunderstorms over parts of the Southeast. Further, moisture over the Southwest and the Central/Southern Rockies, along with diurnal heating, will produce late afternoon into late evening showers and thunderstorms over parts of the Great Basin, Southwest, and Central/Southern Rockies. Meanwhile, a flat upper-level ridge extending from the Four Corners Region eastward to the Mid-Atlantic and Southeast will aid in creating a major to extreme HeatRisk for the East part of the country. The developing heat has prompted Excessive Heat Warnings/Watches and Heat Advisories over parts of the Mid-Atlantic to New England and over parts of the Central/Southern Plains and Middle/Lower Mississippi Valley and parts of the Western Ohio Valley/Western Tennessee Valley. The near-record temperatures and high humidity suggest Major to Extreme HeatRisk conditions for portions of the East, Monday and Tuesday. Extremely dangerous and potentially deadly heat, particularly for urban areas in the Southeast and East Coast, are forecast for Monday and Tuesday. Many daily record highs are possible for the East Coast, and numerous warm overnight lows will provide little relief from the heat overnight. Heat stress will build rapidly for those without adequate cooling or hydration. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php